// Half Adder primitive
module half_adder (
input a, b,
output sum, carry
);
// Write code here
xor (sum, a, b);
and (carry, a, b);
endmodule
// Full Adder using 2 Half Adders
module full_adder_struct (
input a, b, cin,
output sum, cout
);
// Write code here
wire sum1, carry1, carry2;
// First half adder
half_adder ha1(.a(a), .b(b), .sum(sum1), .carry(carry1));
// Second half adder
half_adder ha2(.a(sum1), .b(cin), .sum(sum), .carry(carry2));
// Final OR
or (cout, carry1, carry2);
endmodule